Indicating board for electric power networks



Feb. 7, 1950 G. A. BURNS 6,

INDICATING BOARD FOR ELECTRIC POWER NETWORKS Filed March 50, 1945 IINVENTOR GEORGE ARTHUR BURNS ATTORNEY Patented Feb. 7, 1950 INDICATINGBOARD FOR ELECTRIC POWER NETWORKS George Arthur Burns, Liverpool,England, as-

signor to Automatic Electric Laboratories, Inc., Chicago, 111., acorporation of Delaware Application March 30, 1945, Serial No. 585,669In Great Britain April 27, 1944 2 Claims.

The present invention relates to indicating boards suitable for use insignalling systems for remote supervision and/or control of electricpower transmission systems or the like. It is more particularlyconcerned With boards of the mimic line diagram type built up from aplurality of detachable and interchangeable units or escutcheons each ofthe order of 1 inch square, each unit being either blank or having asymbol thereon depicting a small section of the line diagram of which itforms part.

The object of the invention is to provide an improved form of mimic linediagram of this type in which certain of the escutcheons each depictinga small section of the line diagram carry electric switches forcontrolling the apparatus represented thereby, and in which certainother escutcheons are arranged to be translucent so as to enable thelight from supervisory lamps to be observed therethrough, therebyavoiding lamp cap fittings on the front of the diagram which thuspresents a smooth and pleasing appearance and can readily be kept clean.

According to one feature of the invention, in an indicating board of themimic line diagram type made up of a plurality of detachable andinterchangeable units of identical shape, control equipmentcorresponding to the appropriate units is mounted exclusively behind theboard and is arranged to be effective from the front side without theprovision of any projections or apertures in the front surface so as tomaintain this surface smooth and unbroken.

According to another feature of the invention, in an indicating board ofthe mimic line diagram type made up of a plurality of detachable andinterchangeable units of identical shape, certain of the units forming asection of the line diagram include a rotatable circular portionnormally flush with the front surface the movement of which portion byan attendant is arranged to actuate an electric switch controlling thepiece of apparatus represented by the unit.

A further feature of the invention is that in an indicating board of themimic line diagram type made up of a plurality of detachable andinterchangeable units of identical shape, the individual units are madeof translucent material with a portion of reduced thickness andarrangements are provided for mounting a lamp behind the board closelyadjacent to the reduced portion so that the lightingof the lamp isclearly visible from the front.

The invention will be better understood from the following descriptionof one method of carrying it into effect, reference being bad to theacoompanying drawing comprising Figs. 1 and 2 which show front and sideviews respectively of a portion of an indicating board constructedaccording to the invention, Figs. 3, 4 and 5 which show top views of theescutcheon plates seen in Figure 2, and Fig. 6 which is a crosssectional view showing in detail how the switch escutcheons are mounted.

Referring to Fig. 1, the escutcheon plates such as III are preferablymoulded from plastic material and have square front faces as shown sothat they may be pieced together on the perforated metal panel II tobuild up the complete diagram. The small section of the line diagramdepicted by escutcheon I0 takes the form of a shallow channel which isfilled in with a suitable colouring material. As will be seen from Fig.2 those escutcheons such as Ill which do not carry an electric switchare provided with a stem 12 which passes through a hole in the panel Hand is provided with a circular groove [3 which accommodates the forkedflat spring member M which secures the escutcheon firmly in position onthe panel.

The escutcheon l5 carrying the electric switch is shown more clearly inthe side and cross sectional views. It is provided with a rotatableplastic disc l6, conveniently of the same material as the otherescutcheons, which carries a portion of the line diagram and is normallyflush with the panel. It can, however, be depressed with the finger andturned to actuate the electric contact springs H to perform certaincircuit controlling functions which result in the remote selection ofthe piece of apparatus depicted by this switch in the diagram, forexample a circuit breaker.

As will be seen from Fig. 2 or 6 the rotatable disc I6 is provided witha stem which passes through to the rear of the panel andcarries at itsend an insulating block [8 located between the moving springs of thecontact assembly. Normally, the rotatable disc l6 as seen from Fig. 2 or6 is urged into the position shown, that is, flush with the face of thepanel, by a spring H! which encircles the plunger stem and is housed ina suitable cavity provided partly in the plastic escutcheon and partlyin a metal block 20 which forms a backing member to the panel. Fastenedalso to the metal block 20, by the screws shown, is the L-shaped bracket21 supporting the com tact spring assembly.

When it is desired to open the circuit breaker, represented in the mimicdiagram by the escutchcon I5 in question, the operator depresses withhis finger the rotatable disc l6 against the tension of the spring 19 sothat a plunging action is performed, and the metal backing piece 22turned-over. edges.

located behind the spring operating block [8 is moved axially out ofengagement with a V-shaped locating slot not visible in the drawing.When this is done, the disc I6 can-be rotated so that the portion of theline diagram it carries assumes a horizontal position on the panel thusgiving a pictorial representation of the open condition of the circuitbreaker it represents. In this position the inner contacts of theassembly ll are broken and the outer contacts are made as a result ofdisplacement of the moving springsby theinsulating member l8 which isrectangular in shape and hence its longer dimension assumes a verticalposition when the line on the disc assumes a horizontal position onthe-panel. In thisjposition the member 22 again moves into a V-shapedslot, not visible in the drawing, to locate'the line on the disc in itscorrect horizontal position.

In explanation of the circuit change which takes place as a result ofoperation of the switch,

it should be mentioned that atall times when the switchin the diagramisout of line with the circuit breaker it represents, an indicating lampsuch as 25 is lighted adjacent to the switch, and remains lighted untilsuch time as the indication on the panel ism-agreement with thecondition of the circuit breaker. If the position of the switch ischanged manuallythe lighting of the -lamp may indicate that theassociated circuit breaker hasbeen selected-and can then be made tochange its position by the pressing of a common operate button. Thus inthe case inquestion, when the switch hasbeen operated to bring about -achange ofv condition of the circuit breaker, the

lamp remains alight until the circuit breaker has actually'changed itsposition. Under. other conditions when say the circuitbreakerautomatically trips on fault, the lamp adjacent to the escutcheon lagain lights tocall attention to Y. the difierencein condition of thecircuit breaker and the diagram and remains lit until the-oper- :atorturns the disc to .coincidewith the new posi- .25 are supported byanaL-shaped metal .member '26, the longer limb of which is provided withThese edges enable it to slide on to the upstanding portion of thespring mem- .ber 23 which thus gives the necessary support. A sheetmetal shade orscreen 21 bent into roughly .the'iorm of a cylinderservesto restrict the light to the desired area, namely the reducedcentral .portion of the associated .escutcheon. This mema).

beris provided with turned over edges which .engagein the similar edges.on the. support 28 which. provide lamp mountings maybe. identical withall the other. escutcheons except those carrying switches and as aresult the lamps may readily be moved and located in the position wherethey are most useful. It is found that the indication given by a lamp isreadily visible from the .front of the board, even from a direction ofconsiderable obliquity, and the additional advantage is obtained thatthere isno necessity for lamp caps or the like to break the front faceof thediagram. The lamps may be of any suitable type meeting thedimensional limitations, for instance ofthetype employed inv telephoneexchanges.

The arrangements for securing the special escutcheon to the panel II arenot quite so sim- '20 and thus clamps the escutcheon 5 to the frame I l.

It may be mentioned that if thought desirable the rotatable centreportion of the escutcheons. such as 15 may be provided with a slightlyraisedbar along the line of the diagram so as to facilitate theoperation of turning.

According to the invention therefore a mimic diagram -is; -providedwhich may readily be built up to represent any desired system and whichwhilepermitting control of the circuit breakers and the like from thesymbols which represent them still presents a clear and attractiveappear- .ance which can readily be kept clean.

What I claim as new and desire to secure by Letters Patent is:

1. Inan electrified line diagram board, a base panel havinga pluralityof apertures in spaced ,quadrature relation thereinand a plurality ofsmall interchangeable escutcheons mounted side by side on said panel,stems attached to one face of each of said escutcheons and extendingthrough said panel apertures,.retaining means associated with said.stems foimmaintaining said escutcheons abutting. relationship with saidbase panel, said retainingmeans being concealed from the faces of. saidescutcheonsa mimic pattern defined. by said escutcheons, and electriccontrol switches mounted behind certain of said escutcheons.

2.11111 an electrified line diagram board, a base paneLhaving aplurality of apertures .in spaced quadrature relationship therein, aplurality of small interchangeable. escutcheons mounted sideby-side onsaid panel, stems attachedto one side .of each ,of said escutcheons andextending through said panel apertures, springxmeansassociated with.said stems for maintaining said escutcheons in abutting relationshipwith said base panel, ,saidspringmeansbeing visible only from .the stemside of-said escutcheons, and a mimic patternjdefined by saidescutcheons.

.LGEORGE ARTHUR BURNS.

REFERENCES CITED -,The following references are of record in the le ofthis patent:

UNITED STATES PATENTS Number Name Date 1,963,722 Smith June 19, 19342,010,338 White Aug. 6, 1935 2,028,626 Schleicher etal Jan. 21, 19362,094,134 Obergfell Sept. 28, 1937 2,122,643 Golemb July 5, 19382,221,078 .Dotterer Nov...12, 1940 2,280,438 Matthews Apr. 21, 19422,315,420 Harrington .Mar. 30,1943

. 2,361,412 Baulus et al Oct. 31, 1944 E FOREIGN "PATENTS Number CountryDate 420,629 Great Britain Dec. 5, 1934 .OT-HER REFERENCES The UnitWiring Diagram a New Aid to Works Control,"Helios, August 1939, No. 32,pages 1089, 1090.

